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以典型黑土耕地土壤为研究对象,采用双环入渗仪和染色示踪技术相结合的方法,通过对图片的判读,测定与分析了染色宽度、横纵剖面染色百分比和田间最大染色深度,以研究典型黑土耕地土壤的水分运移形式及其分布特征.结果表明:在0～15cm土层范围内,水分的运移以基质流为主;15～20cm范围内,有侧向入渗发生,平均染色宽度和染色百分比均在此层达到最大值,分别为23cm和20.73%;20～67cm范围内,水分的运移则以大孔隙流为主,优先路径主要是裂缝和大孔隙,其中,20～35cm范围内的大量裂缝使优先流表现出明显的环绕特征;而在40～67cm范围内,优先路径的形成则以连通性良好的大孔隙为主.由于裂缝和大孔隙2种优先路径的存在,使水分在土壤中的运移速度增加了4.5倍,这不仅可能造成水分损失,而且可能加速农药迁移造成地下水污染.建议在黑土区土壤的耕作和经营过程中,应当减少和消除这些优先路径.
Taking typical black soil arable land as the research object, the method of combining the double ring infiltration meter and the dyeing tracing technique was used to analyze and measure the dyeing width, the percentage of dyeing in the longitudinal and longitudinal sections and the maximum depth of dyeing in the field to study The results showed that the main transport of soil water was in the range of 0 ~ 15cm soil depth, lateral infiltration occurred in the range of 15 ~ 20cm, and the average The maximum dyeing width and dyeing percentage reach 23cm and 20.73%, respectively. In the range of 20 ~ 67cm, the migration of water is dominated by macropore flow, and the preferential paths are mainly cracks and macropores. Among them, 20 A large number of fractures in the range of ~ 35cm made the preferential flow show obvious surrounding features, while in the range of 40 ~ 67cm, the preferential routes formed mainly macropores with good connectivity. Because of the two preferential routes of fractures and macropores The water migration in the soil increased by 4.5 times, which not only may cause water loss, but also accelerate the migration of pesticides to cause groundwater pollution.It is suggested that in the cultivation and management of soil in the black soil area, These priority paths should be reduced and eliminated.